It’s an amusing, albeit often highly inconvenient phenomenon that half of the world’s population has to deal with on a regular basis. So what's the scientific story behind that morning glory? Let’s find out.
Morning glories, or nocturnal penile tumescence (NPT), as they are correctly called, are spontaneous erections that occur during sleep or while waking up. All guys without erectile dysfunction are graced with them and they normally occur around three to five times during sleep.
The hormones that can cause erections during the day are kept at the lowest level in the body.
At the end of the day, when you go to sleep and rest, the suppressed hormones are released by the body.
The hormone secretion is greatly increased and naturally, the penis becomes erect, especially after REM sleep
The male hormone testosterone, which increases in the blood, reaches its highest level the moment you wake up.
Since the testosterone is so high, the penis can be erect even though there is no sexual stimulation.
In other words, in most cases, the morning erection is not caused by dreams and sexual thoughts.
Another study came to the following conclusion: During sleep, the nitric oxide secretion increases in the body, and the erection is caused by the fact that this compound expands the blood vessels.
Of course, the penis may be trying to prevent other things from happening. For example, peeing in your bed during sleep.
Finally, a little bit of information: This doesn't only happen to males. Women also have clitoral erections during the nighttime or when they wake up.